Periconceptional maternal folate status and the impact on embryonic head and brain structures: the Rotterdam Periconceptional Cohort.

ABSTRACT

RESEARCH QUESTION Does periconceptional maternal folate status influence the size of human embryonic head and brain structures? DESIGN: The study population was selected from the Rotterdam Periconceptional Cohort conducted at the Erasmus MC. Three-dimensional (3D) ultrasound scans were performed at 9 and 11 weeks of gestational age. Using 3D ultrasound datasets, head volume, head circumference, diencephalon (DTD), mesencephalon (MTD) and left/right telencephalon (TTL/TTR) measurements were performed offline using a virtual reality technique and specialized 3D software. Maternal venous blood samples were taken at study entry to determine red blood cell (RBC) folate. Linear regression models were applied to investigate associations between RBC folate status and embryonic head and brain structures adjusted for gestational age, alcohol use, smoking, maternal age and mode of conception. RESULTS: RBC folate measurements were available for 144 of the 166 singleton pregnancies eligible for analysis. RBC folate quartiles were defined 466-1078 nmol/l (Q1), 1079-1342 nmol/l (Q2), 1343-1594 nmol/l (Q3), 1595-2919 nmol/l (Q4), with Q3 being used as reference. At 11 weeks of gestational age, head volume was largest in Q1 (ß = 0.866; P = 0.004) and Q4 (ß = 0.764; P = 0.007). In addition, head circumference at 11 weeks of gestational age was significantly larger in Q4 (ß = 2.745; P = 0.03). There were no statistical significantly associations between the RBC folate quartiles and the sizes of the DTD, MTD, TTL and TTR. CONCLUSIONS: U-shaped associations were shown between the periconceptional maternal RBC folate status and embryonic head volume and head circumference. The clinical implication of these findings needs further investigation.